BACKGROUND: Operating rooms (ORs) are estimated to generate up to one-third of hospital waste. At the London Health Sciences Centre, prosthetics and implants represent 17% of the institution's ecological footprint. To investigate waste production associated with total knee arthroplasties (TKAs), we performed a surgical waste audit to gauge the environmental impact of this procedure and generate strategies to improve waste management.METHODS: We conducted a waste audit of 5 primary TKAs performed by a single surgeon in February 2010. Waste was categorized into 6 streams: regular solid waste, recyclable plastics, biohazard waste, laundered linens, sharps and blue sterile wrap. Volume and weight of each stream was quantified. We used Canadian Joint Replacement Registry data (2008-2009) to estimate annual weight and volume totals of waste from all TKAs performed in Canada.RESULTS: The average surgical waste (excluding laundered linens) per TKA was 13.3 kg, of which 8.6 kg (64.5%) was normal solid waste, 2.5 kg (19.2%) was biohazard waste, 1.6 kg (12.1%) was blue sterile wrap, 0.3 kg (2.2%) was recyclables and 0.3 kg (2.2%) was sharps. Plastic wrappers, disposable surgical linens and personal protective equipment contributed considerably to total waste. We estimated that landfill waste from all 47 429 TKAs performed in Canada in 2008-2009 was 407 889 kg by weight and 15 272 m3 by volume.CONCLUSION: Total knee arthroplasties produce substantial amounts of surgical waste. Environmentally friendly surgical products and waste management strategies may allow ORs to reduce the negative impacts of waste production without compromising patient care.LEVEL OF EVIDENCE: Level IV, case series.